\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Cross-Candidate Communication and Perceptions of Candidates\label{tab:ccbyideo}}
\begin{tabular}{l*{3}{c}}
\hline\hline
                &\multicolumn{1}{c}{(1)}   &\multicolumn{1}{c}{(2)}   &\multicolumn{1}{c}{(3)}   \\
                &Full Sample   & Liberals   &Conservatives   \\
                &      b/p   &      b/p   &      b/p   \\
\hline
RCV Comp.       &    0.009   &    0.001   &    0.009   \\
                &  (0.560)   &  (0.969)   &  (0.511)   \\
RCV Comp. + Endorse&    0.018   &    0.086***&   -0.061***\\
                &  (0.249)   &  (0.000)   &  (0.000)   \\
Constant        &    0.488***&    0.255***&    0.750***\\
                &  (0.000)   &  (0.000)   &  (0.000)   \\
\hline
R$^2$           &     0.00   &     0.04   &     0.03   \\
\textit{N}      &     2235   &     1175   &     1060   \\
\hline\hline
\end{tabular}
\end{table}
